Approaching from the north the road to this crossing is pretty normal—head south in the middle of Thurso on Rue Galipeau for half a mile and you're at the dock. But from the south, the Ontario side, this is one of the more interesting ferry approaches. The land here rises well above the river, which is wide, with low flat islands and marshy banks. As the road sweeps down to water level you can see the arc of islands in the river, with the ferry approaching. The road crosses a causeway onto Clarence Island, and the ferry docks where the road and the island finish. The causeway and the island take you half way across the river, just leaving the ferry to handle the other half of the crossing.

Driving along the island on our visit we noticed strange things happening on the far bank. It turned out to be a large piece of industrial equipment on a barge being manœuvred onto the shore with a couple of sturdy tugs. There is a paper mill just inland, so the river is probably the easiest way of bringing in large pieces of equipment.

There's a 20 yard channel between the end of the island where the ferry dock is and the next island. In fact looking at maps is seems more like this was once a single mud-bank in the river, and the channel was cut through to improve access for boats, maybe even the precursor of today's ferry. Across this channel on the next island there are a handful of cottages, with just a rickety, narrow floating walkway bridging the gap. But parked beside the walkway is a simple, single-vehicle barge—a "bonus ferry"! It looked like it hadn't been used in a year or two, but could probably be resurrected if the need arose—and you felt brave enough to drive your car onto it.

The ferry service on this route started in the 1920s. In the 1990s the county built the causeway and bridge linking Clarence Island to the mainland, allowing the ferry to use the shorter route. But around 1997 the service was forced to stop due to noise from heavy trucks. In 2005 there was a petition to reinstate the ferry, and it started up again in 2008, now with the trucks banned. Waiting for the ferry at the dock on Clarence Island we could clearly see the original ferry dock on the Ontario shore at the bottom of the hill at the end of the original approach road.

The ferry docks on the Quebec side right beside the Plaisance provincial park which includes lots of trails to walk and bike along, and lots of sheltered water and marshland to canoe, kayak, swim or bird-watch. The small town of Thurso is one more stop on Hwy 148 which links all the villages, towns, cottages and farms that lie on the north shore of this section of the Ottawa River. It is proud of being the birthplace of hockey saint Guy Lafleur, though what we noticed was the sulphurous smell from the pulp and paper factory that we passed as we left the town heading west. A smell that for many Canadians is the smell of money.

The current ferry in fact started life in 1974 serving the Howe Island County route, operated by the Ontario Ministry of Transport. When it was replaced on that route by a bigger vessel it was bought by the owners of this ferry and extensively modified to be powered by electric motors from batteries recharged every night. Hence the Ecolos name. Quieter, non-polluting and a lot cheaper to run.

I'm not saying that other ferry operators don't have pride in their operations, but some of the smaller operations seem to be especially proud, and the Ecolos is one of those. I noted one of the crew eagerly showing off the winding gear to a couple of passengers when we crossed.

Three years after the Ecolos service started there was operational incident. Ice floating in the current accumulated on the upstream side of the ferry as it crossed, causing increased side loads which eventually caused mechanical failure of some of the cable winding machinery on the ferry and of the attachment of one of the two cables on the Thurso side. The ferry then swung around to rest against the shore ice downstream from the Clarence Island dock, the second cable remaining intact and holding the ferry against the current. The passengers and cars on board were safely rescued. As in so many cases the accident resulted from a combination of human and mechanical problems, and improvements have since been made to the machinery. But when we crossed on a fine September afternoon we felt safe and the only problem with the trip was that it was too short to fully enjoy the experience!

The floods of May 2017 affected all the ferries on the Ottawa, causing a lot of closures. On Clarence Island this went well beyond flooding of the ferry dock. I've seen photos of most of the island submerged, including all the road past the bridge.